Coil component and method of manufacturing coil component

Abstract

An inductor conductor is configured such that, with respect to a height-wise dimension of the inductor conductor between the top surface and the bottom surface thereof, the height-wise dimension of a central portion of the top surface is smaller than the height-wise dimension of an edge portion of the top surface at a cross section of the inductor conductor taken in a direction orthogonal to an extending direction of the inductor conductor.

What is claimed is: 
     
         1 . A coil component comprising:
 at least one inductor conductor having
 a top surface and a bottom surface that are positioned opposite to each other and 
 a first side surface and a second side surface that are positioned opposite to each other and connect the top surface and the bottom surface; and 
   a resin-containing layer that at least covers the top surface, the first side surface, and the second side surface of the inductor conductor, wherein   with respect to a height-wise dimension of the inductor conductor between the top surface and the bottom surface, the height-wise dimension of a central portion of the top surface is smaller than the height-wise dimension of an edge portion of the top surface at a cross section of the inductor conductor taken in a direction orthogonal to an extending direction of the inductor conductor, and   in the height-wise dimension of the inductor conductor, a difference between a maximum dimension and a minimum dimension is 20% or less of the maximum dimension at a cross section of the inductor conductor taken in a direction orthogonal to the extending direction of the inductor conductor.   
     
     
         2 . The coil component according to  claim 1 , wherein
 the resin-containing layer includes an insulating resin layer that is an electrical insulator and a non-magnetic body.   
     
     
         3 . The coil component according to  claim 2 , wherein
 the coil component includes a plurality of the inductor conductors, and   the plurality of the inductor conductors is configured such that with respect to the height-wise dimension of each conductor inductor, the height-wise dimension of the central portion of the top surface is smaller than the height-wise dimensions of both edge portions of the top surface at a cross section of each of the inductor conductors taken in a direction orthogonal to an extending direction of the each of the inductor conductors.   
     
     
         4 . The coil component according to  claim 2 , wherein,
 the resin-containing layer integrally configures a portion covering the top surface and portions covering the first side surface and the second side surface.   
     
     
         5 . The coil component according to  claim 1 , wherein
 the resin-containing layer includes a magnetic resin layer made of an organic material containing a metal-based magnetic powder.   
     
     
         6 . The coil component according to  claim 5 , wherein
 the coil component includes a plurality of the inductor conductors, and   the plurality of the inductor conductors is configured such that with respect to the height-wise dimension of each conductor inductor, the height-wise dimension of the central portion of the top surface is smaller than the height-wise dimensions of both edge portions of the top surface at a cross section of each of the inductor conductors taken in a direction orthogonal to an extending direction of the each of the inductor conductors.   
     
     
         7 . The coil component according to  claim 5 , wherein,
 the resin-containing layer integrally configures a portion covering the top surface and portions covering the first side surface and the second side surface.   
     
     
         8 . The coil component according to  claim 1 , wherein
 the resin-containing layer includes
 an insulating resin layer that is an electrical insulator and a non-magnetic body and is in contact with the inductor conductor, and 
 a magnetic resin layer that is made of an organic material containing a metal-based magnetic powder and that covers the insulating resin layer. 
   
     
     
         9 . The coil component according to  claim 1 , wherein
 the coil component includes a plurality of the inductor conductors, and   the plurality of the inductor conductors is configured such that with respect to the height-wise dimension of each conductor inductor, the height-wise dimension of the central portion of the top surface is smaller than the height-wise dimensions of both edge portions of the top surface at a cross section of each of the inductor conductors taken in a direction orthogonal to an extending direction of the each of the inductor conductors.   
     
     
         10 . The coil component according to  claim 1 , wherein,
 the resin-containing layer integrally configures a portion covering the top surface and portions covering the first side surface and the second side surface.   
     
     
         11 . A method of manufacturing a coil component, the method comprising:
 preparing a support substrate;   forming an inductor conductor when supported by the support substrate, the inductor conductor has
 a top surface and a bottom surface that are positioned opposite to each other and 
 a first side surface and a second side surface that are positioned opposite to each other and connect the top surface and the bottom surface; 
   forming a resin-containing layer that at least covers the top surface, the first side surface, and the second side surface of the inductor conductor; and   removing the support substrate, wherein   in the forming of the inductor conductor, with respect to a height-wise dimension of the inductor conductor between the top surface and the bottom surface, the height-wise dimension of a central portion of the top surface is made smaller than the height-wise dimension of an edge portion of the top surface at a cross section of the inductor conductor taken in a direction orthogonal to an extending direction of the inductor conductor, and   in the height-wise dimension of the inductor conductor, a difference between a maximum dimension and a minimum dimension is 20% or less of the maximum dimension at a cross section of the inductor conductor taken in a direction orthogonal to the extending direction of the inductor conductor.   
     
     
         12 . The method of manufacturing the coil component according to  claim 11 , the method further comprising:
 forming a conductive seed layer on the support substrate; and   forming a resist on the seed layer, the resist having a cavity that is patterned so as to correspond to a pattern of the inductor conductor to be formed, wherein   the forming the inductor conductor includes forming the inductor conductor by electrolytic plating on the seed layer through the cavity of the resist, and   the method further comprises removing the resist.   
     
     
         13 . The method of manufacturing the coil component according to  claim 12 , wherein
 the forming the inductor conductor by electrolytic plating includes adjusting additive concentration in a plating bath used for electrolytic plating.   
     
     
         14 . The method of manufacturing the coil component according to  claim 13 , wherein
 the adjusting additive concentration includes increasing a concentration of a leveler additive and of decreasing a concentration of a brightener additive.   
     
     
         15 . The method of manufacturing the coil component according to  claim 12 , wherein
 in the forming of the inductor conductor by electrolytic plating, the seed layer is a seed layer of which a portion corresponding to an edge portion of the top surface of the inductor conductor bulge out relative to a portion corresponding to a central portion of the top surface.   
     
     
         16 . The method of manufacturing the coil component according to  claim 12 , wherein
 the forming the inductor conductor by electrolytic plating includes creating a flow of a plating solution in a plating bath used for electrolytic plating in a direction orthogonal to an extending direction of the inductor conductor to be formed.   
     
     
         17 . The method of manufacturing the coil component according to  claim 12 ,
 in the forming of the inductor conductor by electrolytic plating, the seed layer is made narrower than a width of the cavity of the resist and is formed at a position closer to one of width-wise edges of the cavity.